1. Field of the Invention
The present invention relates to a lighting fixture and a positional information management system.
2. Description of the Related Art
Various positional information management systems have been proposed to determine and manage the position of a wireless terminal, or a person or a thing which has a wireless terminal, in such a facility or the like in which it is difficult to accurately carry out positioning using GPS or the like.
In such a positional information management system, plural transmitters for transmitting positional information to the wireless terminals are installed on the ceiling of a room or the like for example. However, for this purpose, new power supply installation work is needed for supplying power to the transmitters, and thus, the introduction cost may be increased.
International Patent Publication No. 2005/086375 discloses a system in which the position of the wireless terminal is determined as a result of the wireless terminal receiving unique information from a lighting fixture and transmitting the unique information to a server. According to the system of International Patent Publication No. 2005/086375, communication with the wireless terminal is made available using the power supplied to the lighting fixture as a result of providing the lighting fixture with a function of transmitting the unique information to the wireless terminal. Thus, it is not necessary to carry out new power supply installation work at a time of introducing the system.
However, power consumption of the wireless terminal may be increased depending on the communication system employed between the wireless terminal and the server according to the system of International Patent Publication No. 2005/086375. Further, the server needs to search for the position associated with the unique information in order to determine the position of the wireless terminal, and the calculation cost may be thus increased. Further, in a case where the transmitter transmitting the unique information to the wireless terminal is provided in a lamp, the running cost may be increased since the transmitter should be replaced together with the lamp when the lamp has been broken down or come to the end even though the transmitter itself can be further used.